This shows my suction side fitting on the right, and the 2nd one that I plugged off on the left. Tucked behind the filter, you can see the return. (That one did not need cutting.)
On top of the water is the hose for Zippy, my Intex cleaner doing his job on the bottom.
This is how I did the fitting on the inside of the pool for the over the wall skimmer.
The 90 is a "street 90" that I got from Lowes (What do you know... the REAL pool fittings use STANDARD plumbing threads!).
From there, I have one of the barbed hose fittings.
As you can see, the suction is PLENTY for the skimmer to work perfectly, even on LOW.
This is the other barbed fitting (That I have Zippy on the other end of the hose of).
I heated the hose in hot water, and pushed it onto the barb
Zippy doing his thing in a PERFECT TFP pool.